JP2014051447A - Manufacturing method of sulfoxide group-containing palladium supported silica - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a catalyst for a partial hydrogenation reaction, capable of obtaining a partial hydrogenated substrate with a yield equal to or higher than conventional methods which compensate the shortcomings of a Lindlar agent and having no need to use a poisoning agent such as dimethyl sulfoxide.SOLUTION: A sulfoxide group-containing palladium supported silica is obtained by contacting a palladium supported silica and a compound represented by the general formula [1], where R represents an alkylene group having 1 to 6 carbon atoms, Rto Rrepresent each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Rrepresents an alkyl group having 1 to 3 carbon atoms, in a hydrophobic solvent under the presence of water.

Description

  The present invention relates to a method for producing a palladium catalyst suitable for a selective reduction reaction.

  As a method for synthesizing alkenes with high selectivity and without generating byproducts, hydrogenation reaction of alkynes is known. A compound having an unsaturated bond such as an alkene or alkyne is easily reduced in a hydrogen atmosphere by a metal catalyst such as a platinum group element (nickel, palladium, platinum), and a hydrogen atom is added to the unsaturated bond. However, alkenes produced from alkynes are easily reduced to alkanes. Therefore, it has been conventionally difficult to obtain alkenes with high yield and high selectivity from alkynes.

  Currently, a Lindlar reagent is generally used as a method for selectively obtaining an alkene by an alkyne hydrogenation reaction. According to the method using this reagent, in the alkyne hydrogenation reaction, the sequential hydrogenation reaction of the alkene after disappearance of the alkyne can be suppressed, and the alkene can be obtained with high selectivity. However, the Lindlar reagent uses toxic lead, requires quinoline in an amount equal to or more than that of a normal substrate, and further cannot cause a partial hydrogenation reaction from a terminal alkyne, that is, a monosubstituted alkyne to an alkene. Had.

  Under such circumstances, various methods have been reported that compensate for the disadvantages of the Lindlar reagent. For example, a method of performing a partial hydrogenation reaction of an alkyne using a Pd-PEI catalyst in which palladium (Pd) is supported on polyethyleneimine has been reported (Non-Patent Documents 1 and 2). According to this method, alkenes can be obtained in a high yield even for compounds containing a sulfur atom or a nitrogen atom in the molecule in addition to the terminal and internal alkynes.

  In addition, a method for performing a partial hydrogenation reaction of alkyne using a colloidal solution of Pd nanoparticles as a homogeneous catalyst has been reported (Non-patent Document 3). According to this method, various Z-alkenes can be obtained with a high yield of 91.5 to 99.7%.

  Furthermore, a method of performing a partial hydrogenation reaction of alkyne using a catalyst in which Pd nanoparticles are supported on a polyaminoamide dendron having a molecular chain structure with a pyridine structure as a nucleus has been reported (Non-patent Document 4). According to this method, alkenes are obtained in a yield of 96 to 97%.

H. Sajiki, S. Mori, T. Ohkubo, T. Ikawa, A. Kume, T. Maegawa, Y. Monguchi, Chem. Eur. J. 2008, 14, 5109. S. Mori, T. Ohkubo, T. Ikawa, A. Kume, T. Maegawa, Y. Monguchi, H. Sajiki, J. Mol. Cat. A: Chem. 2009, 307, 77. J. Hori, K. Murata, T. Sugai, H. Shinohara, R. Noyori, N. Arai, N. Kurono, T. Ohkuma, Adv. Syn. Catal. 2009, 351, 3143. T. Mizugaki, M. Murata, S. Fukubayashi, T. Mitsudome, K. Jitsukawa, K. Kaneda, Chem. Commun. 2008, 241.

  According to the method as described above, the partial hydrogenation reaction of the substrate can be carried out with high selectivity without using the toxic lead, making up for the disadvantages of the Lindlar reagent. However, in these methods, there is a problem that a partially hydrogenated compound such as an alkene is further hydrogenated (reduced) after an optimum time has elapsed, and a poisoning agent is required. Had a problem. In particular, dimethyl sulfoxide, which is used as a poisoning agent, must be handled with care because it absorbs the skin. Also, since it emits an odor depending on the storage condition and reaction, there is a problem of burden on the operator in addition to the trouble of removal. There was also.

  The present inventors can obtain a partially hydrogenated substrate in a yield equivalent to or higher than the conventional method that compensates for the disadvantages of the Lindlar reagent, and does not require the use of a poisoning agent such as dimethyl sulfoxide. We have been intensively researching about catalysts for chemical reaction. In the process, palladium metal was supported on silica containing a sulfoxide group, and reduction of the alkyne derivative was attempted using the obtained catalyst. In this method, the alkane derivative was reduced to the target alkene derivative. A high yield could not be obtained. However, when a sulfoxide group is introduced into silica carrying palladium metal and the resulting catalyst is used for reduction of an alkyne derivative, hydrogenation from an alkyne derivative to an alkene derivative is highly efficient without using a poisoning agent. As a result, the present invention has been completed. That is, when a compound having a sulfoxide group is reacted with silica carrying palladium metal, the sulfoxide group covers the palladium metal and exerts a poisoning action, and the present invention has been completed.

（式中、Rは炭素数１〜６のアルキレン基を表し、R₁〜R₃は、それぞれ独立して、水素原子又は炭素数１〜３のアルキル基を表し、R₄は炭素数１〜３のアルキル基を表す。）
とを、水の存在下疎水性溶媒中で接触させることを特徴とする、スルホキシド基含有パラジウム担持シリカの製造方法」、「パラジウム担持シリカと下記一般式［１］で示される化合物

（式中、Rは炭素数１〜６のアルキレン基を表し、R₁〜R₃は、それぞれ独立して、水素原子又は炭素数１〜３のアルキル基を表し、R₄は炭素数１〜３のアルキル基を表す。）
とを、水の存在下疎水性溶媒中で接触させることにより得られる、スルホキシド基含有パラジウム担持シリカ」及び「シリカ、パラジウム、及び下記一般式［１］で示される化合物

（式中、Rは炭素数１〜６のアルキレン基を表し、R₁〜R₃は、それぞれ独立して、水素原子又は炭素数１〜３のアルキル基を表し、R₄は炭素数１〜３のアルキル基を表す。）
から得られるものであって、パラジウムの周りを一般式［１］で示される化合物中のスルホキシド基が覆い、一般式［１］で示される化合物中の−Si（OR₁）（OR₂）（OR₃）基がシリカと結合していることを特徴とする、スルホキシド基含有パラジウム担持シリカ」に関する。 The present invention relates to “palladium-supported silica and a compound represented by the following general formula [1].

(In the formula, R represents an alkylene group having 1 to 6 carbon atoms, R _{1 to} R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₄ represents 1 to C carbon atoms. 3 represents an alkyl group.)
In the presence of water in a hydrophobic solvent, a method for producing a sulfoxide group-containing palladium-supported silica "," palladium-supported silica and a compound represented by the following general formula [1]

(In the formula, R represents an alkylene group having 1 to 6 carbon atoms, R _{1 to} R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₄ represents 1 to C carbon atoms. 3 represents an alkyl group.)
And a sulfoxide group-containing palladium-supported silica obtained by contacting with a silica in the presence of water and a compound represented by the following general formula [1]

(In the formula, R represents an alkylene group having 1 to 6 carbon atoms, R _{1 to} R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₄ represents 1 to C carbon atoms. 3 represents an alkyl group.)
In which the sulfoxide group in the compound represented by the general formula [1] is covered around the palladium, and —Si (OR ₁ ) (OR ₂ ) (in the compound represented by the general formula [1]) is obtained. This relates to a sulfoxide group-containing palladium-supported silica, characterized in that the OR ₃ ) group is bonded to silica.

When the sulfoxide group-containing palladium-supported silica obtained by the production method of the present invention is used as a reduction catalyst, an alkene derivative can be produced from an alkyne derivative with a yield equivalent to or higher than that of the conventional method, and the highest yield is obtained. Even after the time for obtaining the alkene derivative (optimum reaction time) has passed, the yield is hardly reduced, so there is no need to take out the alkene derivative at the optimum reaction time, and the yield can be increased more easily. Alkene derivatives can be obtained at a high rate.
Furthermore, when the sulfoxide group-containing palladium-supported silica obtained by the production method of the present invention is used as a reduction catalyst, there is no need to remove a poisoning agent such as dimethyl sulfoxide as in the conventional method, and a simpler method. Is possible. Since it is not necessary to use a poisoning agent, it is not necessary for the operator to pay attention to the handling of the poisoning agent, and it is possible to perform the operation without discomfort such as odor.
Furthermore, since the sulfoxide group-containing palladium-supported silica obtained by the production method of the present invention is a solid catalyst, it can be used as a heterogeneous catalyst, and is excellent in terms of recovery and reuse.

The result of having confirmed the structure of the sulfoxide group containing Pd carrying | support silica catalyst obtained in Example 1 with the transmission electron microscope is represented. The amount of alkenes and the amount of alkanes when the partial hydrogenation reaction was performed with the sulfoxide group-containing Pd-supported silica catalyst obtained in Example 2 are shown.

[Palladium-supported silica]
The palladium-supported silica according to the present invention is a silica supporting palladium. The loading method may be physical loading by adsorption or the like, or chemical loading by ionic bond or the like, but physical loading is preferable.

  The above silica refers to porous silica that can be used as a support. For example, silica gel, specifically, MCM-41 (for example, CT Kresge, et. Al., Nature 359, (1992), p. Synthesized by the method described in 710 etc.), SBA-15 (eg, synthesized by the method described in D. Zhao, et. Al., Science 279, (1998), p.548 etc.), SBA-16 (eg D. Zhao, et. Al., J. Am. Chem. Soc., 120, (1998), p. 6024-6046, etc.), FSM-16 (for example, S. Inagaki et. Al , J. Chem. Soc. Chem. Commun., (1993), p.680 etc.) and other mesoporous silica, fumed silica, porous glass, etc. Examples thereof include crystalline silica such as silicalite, among which amorphous silica is preferable. In addition, these silicas may use a commercially available thing and what was synthesize | combined suitably may be used.

  Representative examples of commercially available amorphous silica include CARiACT-Q-3 (trade name: average pore diameter 3 nm), CARiACT-Q-6 (trade name: average pore diameter 6 nm), CARiACT-Q-10 (product). Name: average pore diameter 10 nm), CARiACT-Q-15 (trade name: average pore diameter 15 nm), CARiACT-Q-30 (trade name: average pore diameter 30 nm), etc. CARiACT series (manufactured by Fuji Silysia Chemical Co., Ltd.) For example, Aerosil (trade name), Aerosil 200 (trade name), Aerosil 300 (trade name), Aerosil 380 (trade name), Aerosil A300 (trade name), Aerosil bs-50 (trade name), Aerosil E300 (trade name) ), Aerosil K7 (trade name), Aerosil M-300 (trade name) and other Aerosil series ( Wonicsil series (manufactured by Wako Pure Chemical Industries, Ltd.) such as Wakosil C-200 (trade name), Wakosil C-300 (trade name), for example, Wako Gel C-100 (trade name), Wakogel series (Wakogel C-200 (trade name), Wakogel C-300 (tradename), Wakogel C-300HG (tradename), Wakogel C-400HG (tradename), Wakogel C-500HG (tradename), etc.) Wako Pure Chemical Industries, Ltd.), among others, CARiACT-Q-3 (trade name: average pore diameter 3 nm), CARiACT-Q-6 (trade name: average pore diameter 6 nm), CARiACT-Q-10 (Trade name: average pore diameter 10 nm), CARiACT-Q-15 (trade name: average pore diameter 15 nm), CARiACT-Q-30 (trade name: flat CARiACT series (manufactured by Fuji Silysia Chemical Co., Ltd.) is preferably a pore diameter of 30nm), etc., CARiACT-Q-30 (trade name: an average pore diameter of 30nm) is particularly preferred.

  Representative examples of commercially available mesoporous silica include, for example, Silica, mesostructured, MCM-41 type (trade name: average pore diameter 2.3-2.7 nm), Silica, mesostructured, HMS (trade name: average pore diameter 3.9 nm), Silica, mesostructured, MSU-H (trade name: average pore diameter 7.1 nm), etc. manufactured by Aldrich, for example TMPS-1.5 (trade name: average pore diameter 1.5 nm), TMPS-4 (trade name: average pore diameter) TMPS series (manufactured by Taiyo Kagaku Co., Ltd.) and the like.

  Palladium in the palladium-supported silica may have a palladium particle size of 0.3 to 10 nm, preferably 1 to 10 nm, more preferably 2 to 8 nm. Pd (0), Pd (I), Pd (II) Pd (0) or Pd (II) is preferable, and Pd (0) is more preferable. The palladium according to the present invention used for supporting is specifically, for example, metal palladium such as palladium oxide, palladium sulfide, palladium chloride, palladium bromide, palladium iodide, palladium hydroxide, palladium nitrate, palladium sulfate, Palladium compounds such as palladium cyanide and palladium acetate, such as bis (acetylacetonato) palladium, diamminedichloropalladium, diamminedinitropalladium, tetraamminepalladium chloride, tetraamminepalladium bromide, tetraamminepalladium nitrate, tetrachloropalladium acid, tetrachloropalladium acid Ammonium, sodium tetrachloropalladate, potassium tetrachloropalladate, lithium tetrachloropalladate, hexachloropalladium Acid, ammonium hexachloropalladate, sodium hexachloropalladate, potassium hexachloropalladate, potassium tetracyanopalladate, potassium tetrathiocyanatopalladate, tetrakistriphenylphosphine palladium, sodium tetrabromopalladate, potassium tetrabromopalladate, hexa Examples include palladium complexes such as sodium bromopalladate, potassium hexabromopalladate, bis (acetonitrile) dichloropalladium, and palladium complexes are preferable, and tetraamminepalladium chloride, tetraamminepalladium nitrate, and sodium tetrachloropalladate are particularly preferable.

  The amount of palladium in the palladium-supported silica according to the present invention is usually 0.1 to 50% by weight, preferably 0.1 to 10% by weight, more preferably 0.1 to 5% by weight, and still more preferably 0.5 to 5% by weight. The amount of palladium may be measured by a method such as inductively coupled plasma-emission spectroscopy (ICP-AES method).

  As a method for producing palladium-supported silica according to the present invention, for example, the palladium according to the present invention is dissolved or suspended in a suitable solvent, and the silica is mixed in the solution, usually for 1 to 30 hours, preferably 1 Impregnated with palladium at 10 to 40 ° C., preferably 20 to 30 ° C. for -20 hours, then dried the silica, and then reduced the supported palladium with alcohol, boron compound or lithium aluminum hydride, hydrogen, etc. As a result, palladium-supported silica is obtained. When the palladium compound is supported on silica by ionic bonding, the reaction may be performed in the same manner as described above except that the pH of the solvent is adjusted to 8 to 12, preferably 9 to 10.

  In the method for producing palladium-supported silica according to the present invention, the palladium according to the present invention may be used singly or in appropriate combination of a plurality of types. The amount of palladium may be added so that the concentration in the solvent is 0.1 to 10 mM, preferably 0.1 to 1 mM. By supporting palladium on the silica with the concentration in the solvent as the above concentration, the palladium particles can be supported on the carrier according to the present invention as nanoparticles.

  Specific examples of the solvent used in the method for producing palladium-supporting silica include water, alcohol solvents such as methanol, ethanol, propanol, and isopropanol, and water-soluble organic solvents such as acetonitrile and acetone. One kind of solvent may be used alone, or a plurality of kinds of solvents may be used in appropriate combination. When the palladium compound is supported by ionic bonds, it is necessary to adjust the pH of the solvent to 8 to 12, preferably 9 to 10. Therefore, water or a combination of water and an alcohol solvent is preferable, and water is particularly preferable. . In addition, as the usage-amount of these solvents, it is 1-1000 mL normally with respect to 1 g of silica, for example, Preferably it is 1-100 mL.

  Examples of the alcohol used for the reduction of palladium in the method for producing palladium-supported silica include alcohols such as methanol, ethanol, propanol, and isopropanol, with ethanol being preferred. The amount of alcohol to be used is not particularly limited, but is usually 1 to 100 mL, preferably 1 to 50 mL, with respect to 1 g of silica, for example. Examples of the boron compound used for the reduction of palladium in the method for producing palladium on silica include sodium borohydride, potassium borohydride, sodium cyanoborohydride, lithium triethylborohydride, trihydride (sec -Butyl) lithium boron, tri (sec-butyl) boron borohydride, lithium borohydride, etc. are mentioned, Among them, sodium borohydride and potassium borohydride are preferable, and potassium borohydride is more preferable. The amount of the boron compound or lithium aluminum hydride to be used is not particularly limited, but is usually 1 to 50 mmol, preferably 1 to 10 mmol with respect to 1 mmol of palladium, for example. When hydrogen is used, the reduction may be performed under a hydrogen atmosphere. The reducing agent such as alcohol, boron compound, lithium aluminum hydride, hydrogen and the like preferably uses the alcohol when the palladium amount in the palladium-supported silica is 0.1 to 1% by weight, and 1% by weight. In the case of exceeding, it is preferable to use a boron compound, lithium aluminum hydride or hydrogen, and it is more preferable to use a boron compound. Further, the reduction is preferably performed by heating to 70 to 90 ° C., preferably 80 to 90 ° C., and stirring for 1 to 4 hours, preferably 1 to 3 hours. Further, it is preferably reduced under an inert atmosphere such as argon.

  The method for drying silica in the method for producing palladium-supported silica is not particularly limited, but is preferably dried under vacuum, and is usually dried for 1 to 10 hours, preferably 5 to 10 hours.

  Specifically, the method for producing palladium-supported silica is, for example, as follows. That is, for example, tetraamminepalladium chloride is dissolved in 100 ml of water so as to be 0.1 to 1 mM, and 1 to 3 g of silica is added. Then, ammonia water is added so that pH may be 9-11, and it is made to react under stirring at 20-40 degreeC for 10-20 hours. After the reaction, the obtained palladium-supported silica is filtered, washed, and dried under vacuum at 10 to 20 ° C. for 5 to 10 hours. Thereafter, 10 to 30 mL of ethanol is added to 1 g of the palladium-supported silica obtained and stirred at 80 to 90 ° C. for 1 to 3 hours under an argon atmosphere. The obtained palladium-supported silica after reduction is washed with ethanol and dried at 10 to 20 ° C. under vacuum to obtain palladium-supported silica. The palladium-supported silica thus obtained is one in which the supported palladium has a particle size of 0.5 to 10 nm and is suitable for the method for producing an alkene derivative of the present invention.

[Compound represented by the general formula [1]]
R in the general formula [1] represents an alkylene group having 1 to 6 carbon atoms, preferably an alkylene group having 1 to 4 carbon atoms, more preferably an alkylene group having 1 to 3 carbon atoms, and a linear or branched group. However, a straight chain is preferable. Specifically, for example, methylene group, ethylene group, n-propylene group, isopropylene group, n-butylene group, isobutylene group, sec-butylene group, tert-butylene group, n-pentylene group, isopentylene group, sec-pentylene. Group, tert-pentylene group, neopentylene group, 2-methylbutylene group, 1,2-dimethylpropylene group, 1-ethylpropylene group, n-hexylene group, isohexylene group, sec-hexylene group, tert-hexylene group, neohexylene group , 2-methylpentylene group, 1,2-dimethylbutylene group, 2,3-dimethylbutylene group, 1-ethylbutylene group, etc., among which methylene group, ethylene group, n-propylene group, n-butylene group Etc., and n-propylene group is more preferable.

The alkyl group having 1 to 3 carbon atoms of R _{1 to} R ₄ in the general formula [1] may be linear or branched, and specifically includes, for example, methyl group, ethyl group, n-propyl group, isopropyl Group, n-butyl group, and the like. Among them, a methyl group and an ethyl group are preferable, and a methyl group is more preferable.

Among the above specific examples, R _{1 to} R ₃ in the general formula [1] are preferably a hydrogen atom or a methyl group, and more preferably a methyl group.

R ₄ in the general formula [1] is preferably a methyl group among the above specific examples.

  Examples of the compound represented by the general formula [1] include methyl-3-trimethoxysilylpropyl sulfoxide, ethyl-3-trimethoxysilylpropyl sulfoxide, propyl-3-trimethoxysilylpropyl sulfoxide, and methyl-3-monomethoxy. Dihydroxysilylpropyl sulfoxide, ethyl-3-monomethoxydihydroxysilylpropyl sulfoxide, propyl-3-monomethoxydihydroxysilylpropyl sulfoxide, methyltrimethoxysilylmethyl sulfoxide, methyl-2-trimethoxysilylethyl sulfoxide, methyl-4-trimethoxy Silylbutyl sulfoxide, methyl-5-trimethoxysilylpentyl sulfoxide, methyl-6-trimethoxysilylhexyl sulfoxide, ethyltrimethoxysilane Methyl sulfoxide, ethyl-2-trimethoxysilylethyl sulfoxide, ethyl-4-trimethoxysilylbutyl sulfoxide, ethyl-5-trimethoxysilylpentyl sulfoxide, ethyl-6-trimethoxysilylhexyl sulfoxide, propyltrimethoxysilylmethyl sulfoxide Propyl-2-trimethoxysilylethyl sulfoxide, propyl-4-trimethoxysilylbutyl sulfoxide, propyl-5-trimethoxysilylpentyl sulfoxide, propyl-6-trimethoxysilylhexyl sulfoxide, methyltriethoxysilylmethyl sulfoxide, methyl- 2-triethoxysilylethyl sulfoxide, methyl-3-triethoxysilylpropyl sulfoxide, methyl-4-triethoxysilylbutyrate Sulphoxide, methyl-5-triethoxysilylheptyl sulfoxide, methyl-6-triethoxysilylhexyl sulfoxide, methyltripropyloxysilylmethyl sulfoxide, methyl-2-tripropyloxysilylethyl sulfoxide, methyl-3-tripropyloxysilylpropyl Examples include sulfoxide, methyl-4-tripropyloxysilylbutyl sulfoxide, methyl-5-tripropyloxysilyl heptyl sulfoxide, methyl-6-tripropyloxysilylhexyl sulfoxide, and the like. Among them, methyltrimethoxysilylmethyl sulfoxide, methyl- 2-trimethoxysilylethyl sulfoxide, methyl-3-trimethoxysilylpropyl sulfoxide, methyl-4-trimethoxysilylbutylsulfoxy And methyl-5-trimethoxysilylpentyl sulfoxide and methyl-6-trimethoxysilylhexyl sulfoxide are preferred, and methyl-3-trimethoxysilylpropyl sulfoxide is more preferred.

（式中、Ｒ及びＲ₁〜Ｒ₃は、上記と同じ。）
下記一般式［２］で示される化合物と

（式中、Ｒ₄は上記と同じ。Xは、ハロゲン原子を表す。）
金属アルコキシドを反応させ、通常1〜１０時間、０〜２０℃で反応させ、得られた下記一般式［１’’］で示されるスルフィド化合物を酸化することにより得られる。

（式中、Ｒ及びＲ₁〜Ｒ₄は、上記と同じ。） The compound represented by the general formula [1] is prepared as follows, for example. That is, a compound represented by the following general formula [1 ′]

(In the formula, R and R _{1 to} R ₃ are the same as above.)
A compound represented by the following general formula [2]:

(In the formula, R ₄ is the same as above. X represents a halogen atom.)
It is obtained by reacting a metal alkoxide, usually reacting at 0 to 20 ° C. for 1 to 10 hours, and oxidizing the obtained sulfide compound represented by the following general formula [1 ″].

(In the formula, R and R _{1 to} R ₄ are the same as above.)

  Specific examples of the compound represented by the general formula [1 ′] include mercaptomethyltrimethoxysilane, 2-mercaptoethyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 4-mercaptobutyltrimethoxysilane, and 5-mercapto. Pentiltrimethoxysilane, 6-mercaptohexyltrimethoxysilane, mercaptomethylmonomethoxydihydroxysilane, mercaptoethylmonomethoxydihydroxysilane, 3-mercaptopropylmonomethoxydihydroxysilane, 4-mercaptobutylmonomethoxydihydroxysilane, 5-mercaptopentylmono Methoxydihydroxysilane, 6-mercaptohexyl monomethoxydihydroxysilane, mercaptomethyltriethoxysilane, 2-mercaptoethyltriethoxy Lan, 3-mercaptopropyltriethoxysilane, 4-mercaptobutyltriethoxysilane, 5-mercaptopentyltriethoxysilane, 6-mercaptohexyltriethoxysilane, mercaptomethyltripropyloxysilane, 2-mercaptoethyltripropyloxysilane, Examples include 3-mercaptopropyltripropyloxysilane, and 3-mercaptopropyltrimethoxysilane is particularly preferable. The compound represented by the general formula [1 '] may be synthesized by a method known per se or a commercially available product may be used.

  Examples of the metal alkoxide include potassium methoxide, potassium ethoxide, sodium methoxide, sodium ethoxide, and sodium isopropoxide. Among them, sodium methoxide and sodium ethoxide are preferable, and sodium methoxide is more preferable.

  The amount of the metal alkoxide to be used is usually 1 to 10 mmol with respect to 1 mmol of the compound represented by the general formula [1 ′].

  Examples of the halogen atom represented by X in the general formula [2] include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among them, iodine is preferable.

  Examples of the compound represented by the general formula [2] include methyl iodide, ethyl iodide, iodopropane, and the like. Among them, methyl iodide is preferable. The usage-amount of General formula [2] is 1-10 mmol normally with respect to 1 mmol of compounds shown by General formula [1 '].

  Specific examples of the sulfide compound represented by the general formula [1 ″] include all compounds in which the sulfoxide group of the compound represented by the general formula [1] is substituted with a sulfide group.

  As a method for oxidizing the sulfide compound represented by the general formula [1 ″], the sulfide may be oxidized to a sulfoxide group according to a method known per se. For example, by oxidizing using an oxidizing agent such as sodium periodate. Good. The amount used, reaction time, reaction temperature, and the like may be appropriately set according to the method usually used in this field.

[Sulfoxide group-containing palladium-supported silica]
The sulfoxide group-containing palladium-supported silica of the present invention is obtained from the above silica, the compound represented by the above general formula [1], and the above palladium, and around the palladium, the compound represented by the general formula [1] In which the —Si (OR ₁ ) (OR ₂ ) (OR ₃ ) group in the compound represented by the general formula [1] is bonded to silica. That is, the compound represented by the general formula [1], centering on palladium, has a structure in which the sulfoxide group is placed on the palladium side so that the palladium is covered, and the compound represented by the general formula [1] is covered by silica. In other words, it has a three-layer structure of palladium, a compound represented by the general formula [1], and silica. The sulfoxide group in the sulfoxide group-containing palladium-supported silica of the present invention is coordinated to palladium.

[Method of producing sulfoxide group-containing palladium-supported silica]
As a method for producing the sulfoxide group-containing palladium-supported silica of the present invention, the palladium-supported silica according to the present invention and the compound represented by the general formula [1] are required in a hydrophobic solvent in the presence of water. For example, by contacting with stirring.

  More specifically, for example, in a suitable hydrophobic solvent, the palladium-supported silica according to the present invention, the compound represented by the general formula [1] (a silane coupling agent having a sulfoxide group) and water are added and mixed. The reaction time is 1 to 20 hours, preferably 5 to 15 hours, usually 50 to 100 ° C., preferably 60 to 90 ° C. If necessary, it is obtained by reacting with stirring.

  The amount of the compound represented by the general formula [1] to be used is generally 10 to 100 mmol, preferably 10 to 50 mmol, with respect to 1 mmol of the palladium-supported silica according to the present invention.

  Examples of the hydrophobic solvent used in the above reaction include aliphatic hydrocarbon solvents such as pentane, hexane, cyclohexane, heptane, octane, isooctane, nonane, decane, diethyl ether, benzene, toluene, xylene, and the like. However, aliphatic hydrocarbon solvents such as pentane, hexane, cyclohexane, heptane, octane, isooctane, nonane and decane are preferred, and heptane is more preferred. These solvents may be used individually by 1 type, or may be used in combination of multiple types as appropriate. The usage-amount of the said solvent is 1-1000mL normally with respect to 1g of silica which carry | supported palladium, Preferably it is 1-100mL.

  The amount of water used in the above reaction is usually 10 to 1000 mmol, preferably 50 to 100 mmol, with respect to 1 mmol of palladium in the palladium-supported silica according to the present invention.

The method for producing the sulfoxide group-containing palladium-supported silica of the present invention is specifically as follows, for example.
That is, after suspending 1 g of palladium-supported silica (about 0.05 mmol as the amount of palladium) in 10 to 50 mL of n-heptane, 1 to 10 mmol of water and 0.5 to 5 mmol of the compound represented by the general formula [1] were added. It is obtained by adding and mixing, and usually reacting with stirring at 50 to 100 ° C. for 10 to 20 hours. After the reaction, if necessary, the precipitate may be filtered and washed with acetone or the like.

[Reduction method using sulfoxide group-containing palladium-supported silica]
The substrate reduction method using the sulfoxide group-containing palladium-supported silica obtained by the production method of the present invention may be carried out in the same manner as a reduction method known per se, except that a poisoning agent is not used. That is, the reduction is performed by reacting the substrate with a hydrogen source in the presence of the sulfoxide group palladium-supported silica.

  The substrate is not particularly limited, but an alkyne derivative is preferable. That is, when the reduction reaction of the alkyne derivative is carried out using the sulfoxide group-containing palladium-supported silica according to the present invention as a catalyst, there is almost no reduction to the alkane derivative, and a partially hydrogenated alkene derivative can be selectively obtained.

（式中、R₁₁は、アルキル基、アルコキシ基、ハロゲン原子、アミノ基及びニトロ基から選ばれる基を置換として有するアリール基、置換基を有さないアリール基、或いはアルキル基を表し、R₁₂は、水素原子、アルキル基、ヒドロキシアルキル基、アルコキシカルボニル基を表す）で示される化合物が挙げられる。
一般式［３］におけるR₁₁で示されるアリール基の置換基であるアルキル基としては、通常炭素数１〜６、好ましくは炭素数１〜３であり、直鎖状、分枝状及び環状のうちのいずれのアルキル基でもよく、具体的には、例えばメチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、イソブチル基、ｓｅｃ−ブチル基、ｔｅｒｔ−ブチル基、シクロブチル基、ｎ−ペンチル基、イソペンチル基、ｓｅｃ−ペンチル基、ｔｅｒｔ−ペンチル基、ネオペンチル基、２−メチルブチル基、１，２−ジメチルプロピル基、１−エチルプロピル基、シクロペンチル基、ｎ−ヘキシル基、イソヘキシル基、ｓｅｃ−ヘキシル基、ｔｅｒｔ−ヘキシル基、ネオヘキシル基、２−メチルペンチル基、１，２−ジメチルブチル基、２，３−ジメチルブチル基、１−エチルブチル基、シクロヘキシル基等が挙げられ、中でもメチル基、エチル基、ｎ−プロピル基、イソプロピル基等が好ましく、メチル基が特に好ましい。 Examples of the alkyne derivative include the following general formula [3]

(Wherein, R ₁₁ is an alkyl group, an alkoxy group, an aryl group having a halogen atom, a group selected from amino and nitro group as a substituent, an aryl group having no substituent, or an alkyl group, R ₁₂ Represents a hydrogen atom, an alkyl group, a hydroxyalkyl group, or an alkoxycarbonyl group).
The alkyl group that is a substituent of the aryl group represented by R ₁₁ in the general formula [3] usually has 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, and is linear, branched or cyclic. Any alkyl group may be used. Specifically, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neopentyl group, 2-methylbutyl group, 1,2-dimethylpropyl group, 1-ethylpropyl group, cyclopentyl group, n-hexyl group, isohexyl group , Sec-hexyl group, tert-hexyl group, neohexyl group, 2-methylpentyl group, 1,2-dimethylbutyl group, 2,3-dimethyl A butyl group, a 1-ethylbutyl group, a cyclohexyl group and the like can be mentioned, among which a methyl group, an ethyl group, an n-propyl group, an isopropyl group and the like are preferable, and a methyl group is particularly preferable.

The alkoxy group which is a substituent of the aryl group represented by R ₁₁ in the general formula [3] may be linear, branched or cyclic, and usually has 1 to 6 carbon atoms, preferably carbon. Specifically, for example, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, tert-butoxy group, n -Pentyloxy group, isopentyloxy group, sec-pentyloxy group, tert-pentyloxy group, neopentyloxy group, n-hexyloxy group, isohexyloxy group, sec-hexyloxy group, tert-hexyloxy group, Examples thereof include a neohexyloxy group, a cyclopropoxy group, a cyclobutoxy group, a cyclopentyloxy group, and a cyclohexyloxy group.

Examples of the halogen atom that is a substituent of the aryl group represented by R ₁₁ in the general formula [3] include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, and among them, a bromine atom is preferable.

As an aryl group in an aryl group having no substituent and an aryl group having a substituent selected from an alkyl group, an alkoxy group, a halogen atom, an amino group, and a nitro group represented by R ₁₁ in the general formula [3] Examples thereof include a phenyl group and a naphthyl group, and among them, a phenyl group is preferable.

Specific examples of the aryl group having a substituent selected from an alkyl group, an alkoxy group, a halogen atom, an amino group, and a nitro group represented by R ₁₁ in the general formula [3] include, for example, a methylphenyl group, an ethylphenyl group, and the like. Group, propylphenyl group, butylphenyl group, pentylphenyl group, hexylphenyl group, methoxyphenyl group, ethoxyphenyl group, propoxyphenyl group, butoxyphenyl group, pentyloxyphenyl group, hexyloxyphenyl group, chlorophenyl group, fluorophenyl group , Iodophenyl group, bromophenyl group, aminophenyl group, nitrophenyl group, methylnaphthyl group, ethylnaphthyl group, propylnaphthyl group, butylnaphthyl group, pentylnaphthyl group, hexylnaphthyl group, methoxynaphthyl group, ethoxynaphth Examples thereof include a til group, propoxynaphthyl group, butoxynaphthyl group, pentyloxynaphthyl group, hexyloxynaphthyl group, chloronaphthyl group, fluoronaphthyl group, iodonaphthyl group, bromonaphthyl group, aminonaphthyl group, nitronaphthyl group and the like.

The alkyl group represented by R ₁₁ in the general formula [3] usually has 1 to 10 carbon atoms, preferably 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, linear, branched and cyclic. Any alkyl group may be used. Specifically, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, n-pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neopentyl group, 2-methylbutyl group, 1,2-dimethylpropyl group, 1-ethylpropyl group, cyclopentyl group, n-hexyl group, isohexyl group , Sec-hexyl group, tert-hexyl group, neohexyl group, 2-methylpentyl group, 1,2-dimethylbutyl group, 2,3-dimethyl Butyl, 1-ethylbutyl, cyclohexyl, n-heptyl, isoheptyl, sec-heptyl, tert-heptyl, neoheptyl, cycloheptyl, n-octyl, isooctyl, sec-octyl, tert -Octyl group, neooctyl group, 2-ethylhexyl group, cyclooctyl group, n-nonyl group, isononyl group, sec-nonyl group, tert-nonyl group, neononyl group, cyclononyl group, n-decyl group, isodecyl group, sec- A decyl group, a tert-decyl group, a neodecyl group, a cyclodecyl group, etc. are mentioned.

Examples of the alkyl group represented by R ₁₂ in the general formula [3] include the same alkyl groups represented by R ₁₁ described above.

The hydroxyalkyl group represented by R ₁₂ in the general formula [3] usually has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms, and may be linear or cyclic. For example, a hydroxymethyl group, 1- Hydroxyethyl group, 2-hydroxyethyl group, 1-hydroxy-n-propyl group, 2-hydroxy-n-propyl group, 3-hydroxy-n-propyl group, 1-hydroxyisopropyl group, 2-hydroxyisopropyl group, 1 -Hydroxy-n-butyl group, 2-hydroxy-n-butyl group, 3-hydroxy-n-butyl group, 4-hydroxy-n-butyl group, 1-hydroxyisobutyl group, 2-hydroxyisobutyl group, 3-hydroxy Isobutyl group, 1-hydroxy-sec-butyl group, 2-hydroxy-sec-butyl group, 3-hydroxy-sec-butyl group Tyl group, 4-hydroxy-sec-butyl group, 1-hydroxy-tert-butyl group, 1-hydroxycyclobutyl group, 2-hydroxycyclobutyl group, 3-hydroxycyclobutyl group, 5-hydroxy-n-pentyl group , 6-hydroxy-n-hexyl group and the like.

The alkoxycarbonyl group represented by R ₁₂ in the general formula [3] usually has 2 to 7 carbon atoms, more preferably 2 to 4 carbon atoms, which may be linear, branched or cyclic, and is a methoxycarbonyl group. , Ethoxycarbonyl group, n-propoxycarbonyl group, isopropoxycarbonyl group, n-butoxycarbonyl group, isobutoxycarbonyl group, sec-butoxycarbonyl group, tert-butoxycarbonyl group, n-pentyloxycarbonyl group, isopentyloxycarbonyl Group, sec-pentyloxycarbonyl group, tert-pentyloxycarbonyl group, neopentyloxycarbonyl group, n-hexyloxycarbonyl group, isohexyloxycarbonyl group, sec-hexyloxycarbonyl group, tert-hexyloxycarbonyl group, neo Hexyloxycarbo Nyl group, cyclopropoxycarbonyl group, cyclobutoxycarbonyl group, cyclopentyloxycarbonyl group, cyclohexyloxycarbonyl group and the like can be mentioned.

  Specific examples of the alkyne derivative represented by the general formula [3] include, for example, propyne, 1-butyne, 2-butyne, 1-pentyne, 2-pentyne, 1-hexyne, 2-hexyne, 3-hexyne, 1- Heptin, 2-heptin, 3-heptin, 1-octyne, 2-octyne, 3-octyne, 4-octyne, 1-nonine, 2-nonine, 3-nonine, 4-nonine, 1-decyne, 2-decyne, Linear alkyne compounds such as 3-decyne, 4-decyne, 5-decyne; 1-phenylethyne, 1-phenyl-1-propyne, 1-phenyl-2-propyne, 1-phenyl-1-butyne, Phenyl-2-butyne, 1-phenyl-3-butyne, 1-phenyl-1-pentyne, 1-phenyl-2-pentyne, 1-phenyl-3-pentyne, 1-phenyl-4-pentyne, 1-phenyl- 1-hexyne, 1-phenyl-2-hex Syn, 1-phenyl-3-hexyne, 1-phenyl-4-hexyne, 1-phenyl-5-hexyne, 1-phenyl-1-heptin, 1-phenyl-2-heptin, 1-phenyl-3-heptin, 1-phenyl-4-heptin, 1-phenyl-5-heptin, 1-phenyl-6-heptin, 1-phenyl-1-octyne, 1-phenyl-2-octyne, 1-phenyl-3-octyne, 1-phenyl-1-octyne Phenyl alkyne compounds such as phenyl-4-octyne, 1-phenyl-5-octyne, 1-phenyl-6-octyne and 1-phenyl-7-octyne; methyl 1-phenyl-1-propinate, 1-phenyl-1 -Ethyl propinate, propyl 1-phenyl-1-propinate, methyl 1-phenyl-1-butyrate, methyl 1-phenyl-1-pentinate, methyl 1-phenyl-1-hexynoate, 1-phenyl Methyl 1-heptinate, methyl 1-phenyl-1-octinate, ethyl 1-phenyl-1-butyrate, ethyl 1-phenyl-1-pentinate, ethyl 1-phenyl-1-hexynoate, 1- Phenyl alkyne esters such as ethyl phenyl-1-heptinate and ethyl 1-phenyl-1-octinate; ethinol, propinol, 2-propinol, 1-butynol, 2-butynol, 3-butynol, 1-pentynol, 2- Pentinol, 3-pentynol, 4-pentinol, 1-hexinol, 2-hexynol, 3-hexynol, 4-hexynol, 5-hexynol, 1-heptinol, 2-heptinol, 3-heptinol, 4-heptinol, 5-heptinol, 6-heptinol, 1-octinol, 2-octinol, 3-octinol, 4-octinol, 5-octinol , 6-octinol, 7-octinol, 1-noninol, 2-noninol, 3-noninol, 4-noninol, 5-noninol, 6-noninol, 7-noninol, 8-noninol, 1-decinol, 2-decinol Alkyne alcohols such as 3-decinol, 4-decinol, 5-decinol, 6-decinol, 7-decinol, 8-decinol, 9-decinol; methylphenylethine, ethylphenylethyne, propylphenylethyne, butylphenylethyne, pentyl Phenylethine, hexylphenylethyne, methoxyphenylethyne, ethoxyphenylethine, propoxyphenylethyne, butoxyphenylethyne, pentyloxyphenylethyne, hexyloxyphenylethyne, aminophenylethyne, 1-aminophenyl-1-propyne, 1- Minophenyl-2-propyne, 1-aminophenyl-1-butyne, 1-aminophenyl-2-butyne, bromophenylethyne, 1-bromophenyl-1-propyne, 1-bromophenyl-2-propyne, 1-bromophenyl -1-butyne, 1-bromophenyl-2-butyne, chlorophenylethyne, chlorophenylethyne, 1-chlorophenyl-1-propyne, 1-chlorophenyl-2-propyne, 1-chlorophenyl-1-butyne, 1-chlorophenyl-2- Butyne, fluorophenylethyne, fluorophenylethyne, 1-fluorophenyl-1-propyne, 1-fluorophenyl-2-propyne, 1-fluorophenyl-1-butyne, 1-fluorophenyl-2-butyne, iodophenylethyne, Iodophenylethyne, 1-iodophenyl-1-propyne 1-iodophenyl-2-propyne, 1-iodophenyl-1-butyne, 1-iodophenyl-2-butyne, nitrophenylethyne, 1-nitrophenyl-1-propyne, 1-nitrophenyl-2-propyne, 1 A phenylalkyne compound having a substituent such as nitrophenyl-1-butyne and 1-nitrophenyl-2-butyne; 1-cyclohexenylethyne, 1-cyclohexenyl-1-propyne, 1-cyclohexenyl-2-propyne, Examples thereof include cyclic alkenyl alkyne compounds such as 1-cyclohexenyl-1-butyne and 1-cyclohexenyl-2-butyne.

（式中、R₁₁及びR₁₂は上記と同じ）。 When the above reduction method is performed using the compound represented by the general formula [3] as a substrate, an alkene derivative represented by the following general formula [4] can be obtained.

(Wherein R ₁₁ and R ₁₂ are the same as above).

The amount of palladium supported silica containing sulfoxide groups in the above reduction method is such that the molar amount of palladium is usually 1 × 10 ⁻⁷ to 1 times, preferably 1 × 10 ^{−5 to} 0.1 times, more preferably 1 mol of the substrate. May be an amount that is 1 × 10 ⁻⁴ to 1 × 10 ⁻² times.

  Examples of the hydrogen source in the reduction method include hydrogen gas, for example, hydrazines such as methyl hydrazine and ethyl hydrazine, such as ammonium formate, and hydrogen gas is preferable. The amount of these hydrogen sources to be used is not particularly limited. For example, the amount is usually set to 1 to 100 mol, preferably 2 to 50 mol, more preferably 2 to 20 mol with respect to 1 mol of the raw material substrate.

  The reduction method is usually 20 to 50 ° C., preferably 20 to 40 ° C., for 1 to 30 hours, preferably 5 to 15 hours.

  The above-mentioned reduction method may be reacted in a solvent, and the solvent is not particularly limited as long as it is usually used in this field, and the amount used may be appropriately set within the range usually used.

  The above reduction method is specifically performed as follows, for example. That is, after the air in the reaction vessel is replaced with hydrogen, 1 to 10 mL of a solvent such as n-hexane containing the substrate is added to the reaction vessel. Thereafter, 1 to 100 mg of the above sulfoxide group-containing palladium-supporting silica containing 1 to 10 μmol of palladium and 0.1 to 1 mmol of the substrate are added to the solvent and reacted at 20 to 40 ° C. for 5 to 15 hours. After the reaction, the reaction product can be obtained by removing the catalyst according to the present invention by filtration and evaporating the reaction solvent.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

MPTMS（メルカプトプロピルトリメトキシシラン、東京化成工業（株）製） 19.6 g（100 mmol）とナトリウムメトキシドを28％含有するメタノール溶液 20g（NaOMeとして100mmol）の混合溶液を100 mL三つ口フラスコに加え、滴下ロートを装着し反応容器内をアルゴン置換した後、氷冷した。滴下ロートを用いてヨウ化メチル（和光純薬工業（株）製） 16.6 g（110 mmol）を滴下した。滴下終了後、室温で1時間撹拌した後、反応管内を真空引きし、メタノールを蒸発させた。生成物をヨウ化メチレン（CH₂Cl₂）で抽出してろ過によりナトリウムメトキシド（NaOMe）およびヨウ化ナトリウム（NaI）を分離し、液相をエバポレーターにより濃縮後、減圧蒸留し、メチルトリメトキシシリルプロピルスルフィド（MeSPrTMS、沸点：95℃, 4mmHg）を得た（収率：80%）。
次いで、100 mLナス型フラスコに、得られたMeSPrTMS2.26 g（10 mmol）、メタノール20 mL、2,6−ターシャルブチル−p−クレゾール（和光純薬工業（株）製） 0.01 gを加え、アルゴン置換した後、反応器を氷冷し、過ヨウ素酸ナトリウム（NaIO₄、和光純薬工業（株）製）2.4 g（12 mmol）を加え、氷浴中で24時間撹拌した。得られた液体を濾過後、エバポレーターにより濃縮し、メチル−トリメトキシシリルプロピルスルホキシド（MeSOPrTMS）を得た（収率：62%） Example 1 Method for producing sulfoxide group-containing Pd-supported silica catalyst (Pd / SiO ₂ -Sulfoxide) (1) Synthesis of methyl-trimethoxysilylpropyl sulfoxide (MeSOPrTMS)

MPTMS (Mercaptopropyltrimethoxysilane, manufactured by Tokyo Chemical Industry Co., Ltd.) 19.6 g (100 mmol) and a mixed solution of 20 g of methanol solution containing 28% sodium methoxide (100 mmol as NaOMe) in a 100 mL three-necked flask In addition, a dropping funnel was attached and the inside of the reaction vessel was purged with argon, followed by ice cooling. 16.6 g (110 mmol) of methyl iodide (manufactured by Wako Pure Chemical Industries, Ltd.) was added dropwise using a dropping funnel. After completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour, and then the inside of the reaction tube was evacuated to evaporate methanol. The product is extracted with methylene iodide (CH ₂ Cl ₂ ), and sodium methoxide (NaOMe) and sodium iodide (NaI) are separated by filtration. The liquid phase is concentrated by an evaporator and distilled under reduced pressure. Silylpropyl sulfide (MeSPrTMS, boiling point: 95 ° C., 4 mmHg) was obtained (yield: 80%).
Next, to the 100 mL eggplant-shaped flask was added MeSPrTMS2.26 g (10 mmol), methanol 20 mL, 2,6-tert-butyl-p-cresol (manufactured by Wako Pure Chemical Industries, Ltd.) 0.01 g. After replacing with argon, the reactor was ice-cooled, 2.4 g (12 mmol) of sodium periodate (NaIO ₄ , manufactured by Wako Pure Chemical Industries, Ltd.) was added, and the mixture was stirred in an ice bath for 24 hours. The obtained liquid was filtered and then concentrated by an evaporator to obtain methyl-trimethoxysilylpropyl sulfoxide (MeSOPrTMS) (yield: 62%)

(2) Preparation of Pd-supported silica (Pd / SiO ₂ ) Take 5 mL of concentrated aqueous ammonia (28 wt%) in a flask, add 0.2 g of palladium chloride (PdCl ₂ ), and stir well at 100 ^° C for 30 minutes. Palladium was dissolved. The resulting pale yellow transparent solution was filtered to remove undissolved palladium chloride. When 50 mL of ethanol is poured into the filtrate, white Pd (NH ₃ ) ₄ Cl ₂ • H ₂ O precipitates, which is filtered and dried under vacuum for 1 hour to obtain Pd (NH ₃ ) ₄ Cl ₂ . It was.
In 100 mL eggplant type flask, dissolved in the resulting _{Pd (NH 3) 4 Cl 2} · H 2 O0.0131 g (0.05 mmol) were added deionized distilled water _{50 mL, SiO 2 [CARiACT Q} -30 ( 200-350 mesh), manufactured by Fuji Silysia Chemical Co., Ltd.], 1.0 g was added, and concentrated aqueous ammonia was added dropwise using a pipette while the solution was stirred to adjust the pH to 10. The flask was stoppered and stirred as it was at 30 ^° C. for 12 hours in an air atmosphere. The obtained slurry was filtered, washed with about 1 L of deionized distilled water until the filtrate became neutral, and then vacuum-dried at 30 ^° C. for 6 hours in a desiccator to obtain white powder of Pd-supported silica ( Pd ^II SiO ₂ , 0.95 g) was obtained.
Next, add the prepared Pd-supported silica to a 100 mL eggplant flask with a branch, attach a reflux tube and a three-way cock with a gas back, evacuate with a pump for 30 minutes, purge the reaction tube with argon, and add 20 mL of ethanol. And stirred at 85 ^° C. for 2 hours. The obtained powder was suction filtered, washed with 200 mL of ethanol, and vacuum-dried in a desiccator at 30 ^° C. for 2 hours. Pd / SiO ₂ (0.85 g, Pd content: 0.047 mmol) as a brownish gray powder / G) was obtained.

(3) Pd / SiO ₂ containing sulfoxide groups
Furthermore, the obtained Pd / SiO ₂ (1.0 g, Pd content: 0.047 mmol / g) was added to a 100 mL eggplant-shaped eggplant flask, fitted with a three-way cock with a gas bag, and evacuated with a pump for 30 minutes. The inside of the tube was purged with argon, 20 mL of n-heptane and 0.090 g (5 mmol) of water were added, and the mixture was stirred at room temperature for 1 hour. Subsequently, 0.226 g (1 mmol) of MeSOPrTMS synthesized in (1) was added, followed by stirring at 80 ^° C. for 12 hours. The resulting precipitate was filtered by suction, washed 5 times with 20 mL of acetone, and then vacuum-dried to obtain a catalyst (sulfoxide group-containing Pd / SiO ₂ ).
The result of confirming the structure of the obtained sulfoxide group-containing Pd / SiO ₂ with a transmission electron microscope is shown in the left figure of FIG. The right figure shows a schematic diagram of the structure.
From the left figure of FIG. 1, it was speculated that the sulfoxide group-containing Pd / SiO ₂ had a structure in which a sulfoxide group was bonded to palladium, and the periphery thereof was covered with silica gel.

Example 2 Partial hydrogenation reaction of alkyne with sulfoxide group-containing Pd / SiO _{2 To the} Schlenk tube, 0.050 g (Pd content: 2.3 μmol) of sulfoxide group-containing Pd / SiO ₂ obtained in Example 1 was added, and three-way with gas back A cock was attached. The inside of the reactor was evacuated with a pump for 30 minutes, and then the inside of the reactor was replaced with hydrogen three times by repeated substitution and degassing with hydrogen, and finally, hydrogen was charged. 5 mL of n-hexane and 0.5 mmol of 1-phenyl-1-propyne were added to the reactor, and the reaction time was set to 10 to 180 minutes at 30 ^° C. to carry out a hydrogenation reaction. The catalyst was removed from the reaction product for a predetermined time by filtration, and the filtrate was evaporated by an evaporator to recover the product. A pure product was obtained from the residue by silica gel column chromatography (WAKOGEL C-200, developing solvent n-hexane: AcOEt). The product was identified by gas chromatography (GC), GC-MS, and NMR, and quantification was performed by GC using naphthalene as an internal standard. The result is shown in FIG. In FIG. 2,-♦-represents the yield of alkene (compound 2), and-●-represents the yield of alkane (compound 3).
The yields of compounds 2 and 3 at 120 minutes and 180 minutes are shown in Table 1 below.

From the above results, it was found that when sulfoxide group-containing Pd / SiO ₂ was used, the partial hydrogenation reaction proceeded with high selectivity, and the alkene could be obtained with a yield of 94%. It was also found that after the disappearance of the substrate, the hydrogenation reaction to alkane hardly progressed even if the reaction time was extended.

Comparative Example 1 Method for producing a catalyst in which palladium metal is supported on sulfoxide group-containing silica (1) Method for producing sulfoxide group-containing silica
Add SiO ₂ (1.0 g) to a 100 mL eggplant flask with a branch, attach a three-way cock with a gas back, and evacuate with a pump for 30 minutes. Then, the reaction tube is purged with argon, 20 mL of n-heptane, 0.090 g of water ( 5 mmol) was added and stirred at room temperature for 1 hour. Subsequently, 0.226 g (1 mmol) of MeSOPrTMS synthesized in (1) was added, followed by stirring at 80 ^° C. for 12 hours. The resulting precipitate was filtered by suction, washed 5 times with 20 mL of acetone, and then vacuum-dried to obtain sulfoxide group-containing silica.
(2) Method for producing a catalyst in which palladium metal is supported on silica containing sulfoxide groups
Pd (NH ₃ ) ₄ Cl ₂ · H ₂ O (0.0131 g, 0.05 mmol) was added to a 100 mL eggplant-shaped flask and dissolved in 50 mL of deionized distilled water, and 1.0 g of the resulting sulfoxide-containing silica was added. The flask was stoppered and stirred as it was at 30 ^° C. for 12 hours in an air atmosphere. The resulting slurry was filtered, washed with about 1 L of deionized distilled water until the filtrate became neutral, and then vacuum-dried at 30 ^° C for 6 hours in a desiccator, containing yellow powdered Pd-supported sulfoxide 0.95 g of silica was obtained.
Next, add the prepared Pd-supported sulfoxide-containing silica to a 100 mL eggplant flask with a branch, attach a reflux tube and a three-way cock with a gas back, evacuate with a pump for 30 minutes, purge the inside of the reaction tube with argon, and add 20 mL of ethanol. And heated and stirred at 85 ^° C. for 2 hours. The obtained powder was suction filtered, washed with 200 mL of ethanol, and then vacuum-dried at 30 ^° C for 2 hours with a desiccator to prepare a catalyst in which palladium metal was supported on silica containing sulfoxide groups, which was a brownish gray powder. Obtained.

Comparative Examples 2-3 Reduction Method of Alkyne by Catalyst with Palladium Metal Supported on Sulphoxide Group-Containing Silica Palladium Metal was Supported on Sulphoxide Group-Containing Silica Obtained in Comparative Example 1 Instead of 0.050 g of Pd / SiO ₂ Containing Sulphoxide Group The hydrogenation reaction of 1-phenyl-1-propyne was carried out in the same manner as in Example 1 except that 0.2 g (1 μmol) of the catalyst was used and the reaction time was 10 minutes or 25 minutes. The results are shown below.

From the results shown in Table 2, in the catalyst in which palladium metal is supported on sulfoxide group-containing silica, the alkyne derivative is hydrogenated like the catalyst obtained by the production method of the present invention (the catalyst in which sulfoxide group is introduced into palladium-supported silica). Thus, it was found difficult to obtain the alkene derivative with high efficiency.
This was thought to be due to the difference in the structure of the catalyst. That is, according to the production method of the present invention, since the sulfoxide group of the sulfoxide group-containing compound is first bonded to palladium, and then the trimethoxysilyl group is bonded to silica, the palladium is almost completely covered with the sulfoxide group. It was speculated that On the other hand, when palladium metal was supported on sulfoxide group-containing silica, the sulfoxide group was supported on silica and could not move freely, so it was assumed that palladium was not completely covered with sulfoxide groups.

Comparative Examples 4 to 5 Reduction method of alkyne with Pd / SiO ₂ (no poisoning agent)
A partial hydrogenation reaction of 1-phenyl-1-propyne was carried out in the same manner as in Example 2 except that Pd / SiO ₂ was used as a catalyst and the hydrogenation reaction was carried out for a predetermined time in the following table. The product was quantified in the same manner as in (Comparative Example 4).
Similarly, an experiment was conducted for the case where dimethyl sulfoxide was added as a poisoning agent and 2 mol% or 0.6 mol% of the substrate was added, and the product was quantified (Comparative Examples 5 to 7). These results are shown below.

From the result of Comparative Example 4, when the alkyne hydrogenation reaction was carried out using Pd / SiO ₂ in the absence of a poisoning agent, the alkene yield was 72% at a reaction time of 15 minutes. It was found that the reduction selectivity to alkene rapidly decreased with the progress of sequential hydrogenation reaction and hydrogenated to alkane. On the other hand, from the results of Comparative Example 5, it was shown that the addition of dimethyl sulfoxide, which is a poisoning agent, yields an alkene derivative efficiently. However, in this case, the yield of the compound was measured after removing dimethyl sulfoxide, and there were problems of odor and troublesome operation. In Comparative Examples 6 and 7, sulfoxide group-containing Pd / SiO ₂ used in Example 2 was equivalent to sulfoxide group (6 mmol with respect to 1 mmol of palladium) and dimethyl sulfoxide (6 mmol with respect to 1 mmol of palladium). ) Is used for the reaction. However, in this case, alkenes could not be obtained with high selectivity. That is, when a poisoning agent such as dimethyl sulfoxide is used, it is necessary to appropriately set the amount of these used, and a larger amount of sulfoxide groups than the amount of sulfoxide groups used in the sulfoxide group-containing Pd / SiO _2. It was found that alkyne to alkene could not be reduced with high selectivity unless (dimethyl sulfoxide) was used.

Examples 3 to 18 Partial hydrogenation reaction of various alkynes with sulfoxide group-containing Pd / SiO ₂ Instead of 0.5 mmol of 1-phenyl-1-propyne as the substrate, 0.5 mmol of various substrates in Table 4 were used, and the reaction temperature and reaction Various alkyne partial hydrogenation reactions were performed in the same manner as in Example 2 except that the time was set to the predetermined time shown in Table 4.
The yields of the corresponding alkene compounds (formula 2) obtained by the reaction are shown in Tables 4 and 5 below.

  From the above results, it was found that as a result of hydrogen reduction of various alkene derivatives using the catalyst obtained by the method of the present invention, any of the alkene derivatives can be produced efficiently.

  In FIG. 2,-♦-represents the yield of alkene (Compound 2) in Example 2, and-●-represents the yield of alkane (Compound 3) in Example 2.

Claims (7)

Palladium-supported silica and a compound represented by the following general formula [1]

(In the formula, R represents an alkylene group having 1 to 6 carbon atoms, R _{1 to} R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₄ represents 1 to C carbon atoms. 3 represents an alkyl group.)
In a hydrophobic solvent in the presence of water, a process for producing palladium-supported silica containing a sulfoxide group. The production method according to claim 1 or 2, wherein the palladium-supporting silica is silica on which palladium metal having a particle diameter of 0.3 to 10 nm is physically supported. The production method according to claim 1 or 2, wherein R _{1 to} R ₃ are all methyl groups. The manufacturing method in any one of Claims 1-3 whose R is a C1-C3 alkylene group. The hydrophobic solvent is one or more solvents selected from pentane, hexane, cyclohexane, heptane, octane, isooctane, nonane, decane, diethyl ether, benzene, toluene, and xylene. Manufacturing method. Palladium-supported silica and a compound represented by the following general formula [1]

(In the formula, R represents an alkylene group having 1 to 6 carbon atoms, R _{1 to} R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₄ represents 1 to C carbon atoms. 3 represents an alkyl group.)
And sulfoxide group-containing palladium-supported silica obtained by contacting with a sulfoxide group in a hydrophobic solvent in the presence of water. Silica, palladium, and a compound represented by the following general formula [1]

(In the formula, R represents an alkylene group having 1 to 6 carbon atoms, R _{1 to} R ₃ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and R ₄ represents 1 to C carbon atoms. 3 represents an alkyl group.)
The sulfoxide group in the compound represented by the general formula [1] covers the periphery of palladium, and —Si (OR ₁ ) (OR ₂ ) (in the compound represented by the general formula [1] is obtained. A palladium-supported silica containing a sulfoxide group, wherein an OR ₃ ) group is bonded to silica.

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